A composite comprising
Ti and NaCl powders was sintered similar
to a three-dimensional (3D)-printed patient-customized artificial
bone scaffold. Additionally, a proper microstructure of the mimetic
scaffold and the optimum processing parameters for its development
were analyzed. The mechanical properties of the metal-based porous-structured
framework used as an artificial bone scaffold were an optimum replacement
for the human bone. Thus, it was confirmed that patient-customized
scaffolds could be manufactured via 3D printing. The 3D-printed mimetic
specimens were fabricated by a powder-sintering method using Ti for
the metal parts, NaCl as the pore former, and polylactic acid as the
biodegradable binder. Scanning electron microscopy (SEM) images showed
that pores were formed homogeneously, while X-ray computed tomography
confirmed that open pores were generated. The porosity and pore size
distribution were measured using a mercury porosimeter, while the
flexural strength and flexural elastic modulus were calculated using
the three-point bending test. Based on these measurements, a pore-former
content of 15 vol % optimized the density and flexural strength to
2.52 g cm
–2
and 283 MPa, respectively, similar to
those of the actual iliac bone. According to the 3D-printing production
method, a selective laser-sintering process was applied for the fabrication
of the mimetic specimen, and it was determined that the microstructure
and properties similar to those of previous metal specimens could
be achieved in the as-prepared specimen. Additionally, a decellularized
extracellular matrix (dECM) was used to coat the surfaces and interiors
of the specimens for evaluating their biocompatibilities. SEM image
analysis indicated that the adipose-derived stem cells grew evenly
inside the pores of the coated specimens, as compared with the bulky
Ti specimens without the dECM coating. The doubling time at 65% was
measured at 72, 75, and 83 h for specimens with pore-former contents
of 5, 10, and 15 vol %, respectively. The doubling time without the
pore former was 116 h. As compared with the specimens without the
pore former (73 h), 15% of the dECM-coated specimens showed a doubling
time of 64%, measured at 47 h.